[PATCH] fanotify_user: use upper_32_bits() to verify mask

From: Christian Brauner
Date: Thu Mar 25 2021 - 04:40:32 EST


From: Christian Brauner <christian.brauner@xxxxxxxxxx>

I don't see an obvious reason why the upper 32 bit check needs to be
open-coded this way. Switch to upper_32_bits() which is more idiomatic and
should conceptually be the same check.

Cc: Amir Goldstein <amir73il@xxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
---
fs/notify/fanotify/fanotify_user.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 9e0c1afac8bd..d5683fa9d495 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1126,7 +1126,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
__func__, fanotify_fd, flags, dfd, pathname, mask);

/* we only use the lower 32 bits as of right now. */
- if (mask & ((__u64)0xffffffff << 32))
+ if (upper_32_bits(mask))
return -EINVAL;

if (flags & ~FANOTIFY_MARK_FLAGS)

base-commit: 0d02ec6b3136c73c09e7859f0d0e4e2c4c07b49b
--
2.27.0